In the wake of Forever 21’s Sunday bankruptcy filing, the retailer has taken pains to tell customers that it’s not going out of business — but the news does seem to mark the end of an era.

The fast-fashion chain is just the latest in a long line of teen-geared, mostly-mall-based retailers to go bankrupt in recent years, following peers like Charlotte Russe, Claire’s, Wet Seal, Papaya, Rue21, Aeropostale, PacSun and Delia’s. All live on (in name at least), though many are under new management and most have drastically reduced their store counts, if they haven’t gone online-only.

Forever 21, too, says it expects to close about 350 stores, including up to 178 in the U.S. (currently, it has 549 U.S. locations and 251 internationally). In an open letter posted on its website, it calls the reorganization “a deliberate and decisive step to put us on a successful track for the future.”

The 35-year-old retailer likely has a tough road ahead, however, experts say. One obstacle is simply the cohort it has historically targeted: teenagers.

“This has traditionally has been the most fickle of all the demographics to chase,” said Marshal Cohen, chief industry advisor at The NPD Group, a market research firm. “You’re in today and you’re actually, in today’s world, out today — not even tomorrow. And that revolving door of that constantly new customer base, there’s not a long period of time for loyalty.”

That’s not to say that teen retailers can’t win — Gen Z consumers spend an estimated $143 billion per year in the U.S. and influence up to $127.5 billion more, according to a 2018 report by the advertising firm Barkley. But to do so, they need to adapt to rapidly evolving tastes, which today favor a wide array of brands over

“One of the reasons why you would have thought that Forever 21 would have done really well during this period is young people don’t buy the uniforms that they used to use to buy in the 90s and the early Aughts,” said Lee Peterson, EVP of thought leadership and marketing at WD Partners, a retail and customer experience consultancy.

When millennials and Gen Xers were teens, they might have gone to Abercrombie & Fitch or the Gap and stocked up on logo tees, sweatshirts, jeans and hats all from the same store. “That just isn’t happening anymore,” he said.

Looking to the future, this could mean that the playing field for teen retailers will be broader, but with fewer clear winners. “Younger shoppers like to shop around and mix brands and styles, so it’s unlikely that there will be one dominant one as there have been in years past with retailers like Abercrombie & Fitch or even Limited Too,” said Tiffany Hogan, a senior analyst, consulting division at Kantar, a research, data and insights company.

Forever 21 has never been heavy on logos or branding, which should have helped it succeed, said Peterson. “They’ve just got a bunch of stuff in their stores and its super cheap,” he said. But its ambitious expansion in recent years — which saw it lease hundreds of massive stores, largely in shopping malls — ignored the realities of today’s retail business.

While research suggests that Gen Z consumers prefer physical stores to online shopping, many of the country’s malls have seen falling foot traffic and increasing vacancies as anchor stores such as Macy’s, Sears and J.C. Penney have reduced their brick-and-mortar footprints. While the top shopping centers are healthier than ever (many of them having invested heavily in better food and entertainment options and other modern amenities), their less profitable peers aren’t drawing the crowds needed to pay rent on such large stores. (The average Forever 21 store is 38,000 square feet, while the largest is 162,000 square feet.)

As Cohen put it: “You can build something as big as a supermarket, but you better get people coming in every day to buy.”

By this token, Peterson sees Urban Outfitters as a strong contender to take up Forever 21’s mantle, with its varied portfolio of brands (apart from its namesake, it owns the fashion retailers Free People and Anthropologie, the pizza chain Vetri Family and the clothing rental subscription service Nuuly) and its willingness to invest to reach consumers through new channels (as the latter two ventures suggest). UO is also less reliant on malls and its stores carry a wide variety of categories, including a significant array of accessories, home goods, vinyl records, gifts and more.

Other low-price retailers such as H&M and Zara could benefit from Forever 21’s consolidation, but they aren’t guaranteed bets, as H&M’s inventory struggles last year made clear. “There are risks in the fast-fashion model,” said Greg Portell, lead partner in the global consumer and retail practice of A.T. Kearney, a strategy and management consulting firm. “There is less margin for error — particularly as companies grow. If a retailer misreads the trends, they end up with the wrong inventory positions at higher volumes. As a result, they wind up paying a higher cost both in missed opportunity and in the need to discount or dump.”

Gen Z is also more focused on sustainability than previous generations, making fast fashion a potentially tough sell for many consumers. Here, resale apps such as Depop could emerge as an increasingly important contender for teen dollars. Depop recently closed a $62 million funding round to expand in Europe and Asia, and currently has more than 13 million users — most of them under age 26. It currently has brick-and-mortar spaces in New York and Los Angeles, as well as a pop-up in London, but the question is: will it continue to build its footprint?